Self-aligning carrier



2 Sheets-Sheef 1 Filed July 18, 1950 INVENTOR. R G. LETOURNEAU AGfNTPatented Jan. 5, 1954 to R..'G. Le Tourneau ofalifornia Inc., Peoria,111., a corassu s JuIylS 1950 Serial'No; 174 .456 '7 cl ims, (01.191F202) invention relates; to. Lelt'type carriers. or. conveyorsandmore particularly to such. a carrier that. is-conveyed over rolls.

It is extremely diflicult to keep carriersfoi any length in the. properalignmentv on their rolls. and sometype of adjusting means is usuallyrequired for-satisfactory operation. This is especially true where thebelt travels. at a high speed suchas in earth. loading, mamhines- The.tendency in these operations is'ior the belt to creep to one side or theother oi the roll and if not corrected, the belt. could work completelyon the rolls,v or damage. it-' self on. adjacent equipment.

It is therefore. the primary object. of this in:- venticn to provide amechanism (for automati Fig. 1) and over a power driven head pulley Hcally aligning a. carrier belt'onj its rolls at the first indicationthat the belt is riding to, one. side Another object of this inventionis to provide a means for preventing. the alignment mechanism fromsending the belt too far in the other direction when making theadjustment.

A; further object of this invention is to provide an electricallyactuated linkage which'w'ill move the troughing' roll in one directionand the carrier rollinthe other direction to. better align. the beltwhich. is traveling in opposite directions over each- Theseand otherobjects will be apparent from a perusal oi the following specificationand drawin which:

Fig. 1 represents a plan view of the carrierwith aportion of the beltcutaway to show the alignment mechanism of this invention The trough ingrolls and. one roller "8 and associated parts have been omitted fromthis view for clarity of illustration.

Fig. .2is an elevational view of the mechanism including the troughingand carrier rolls taken in section along lines 2-2 of Fig. 1 v I Fig.3'is a section taken along the lines 3- 3 of Fig. 1.

[Fig d is a side elevational view of the carrier showing therelationship of the various rolls thereoft Referring now moreparticularly (to the drawings, a. carrier containing the instantinvention is seento consist of a frame ljincluding'sld'e arms 2 audiospaced apart'by means of cross members 3. Troughing rolls 4 are vjournalledin crossmem bets 3-, on the top oi which rolls an endless belt5 rides. The self-aligning troughing rolls 4a are journalled in apivoted cross member 3a, and die rectly beneath a carrier roll 6 is,journalledin a second pivoted cross member 1.

The belt 5 travels up the incline (as shown in and thenreversing; its.direction, travels. over snubbing roll R and through a floatin snubberstructure. S,.and at the lower endof the 'c arrier the belt passesaround direction changing pulley D to complete its. cycle.

Near the. top of the carrier frame I a guide roller 8. is journalled asat. 9 in a'bracket. H1 which is. pivoted. as. a unit, to mount l by p n12. This bracket H1 is free. to. pivot about pin. [2 under the urging ofbelt 5 until it. strikes. bolt l3 of stop bracket l4. Howeverjust priorto. engagement with bolt [3 the. acket .10 by means of attached pad.will depress plunger lo of. aynormally of! switch ll. attached to. frameI. This switch I"! will actuate a. small. reversible motor [8 which willthrough its pinion lll'cause gear and attached lead screw 21 to rotate.head screw 21' includes threads 21 which. cooperate with thr ds no:sleeve 24 to. cause sleeve. 24. to advance or retract according to the.direction of. rotation of motor l 8. Sleeve 24 pivoted .by means of. pin25 to pivot bar 26. Motor [8 and attached gear housing bracket 28 arepivoted by means of pin '2'! and bracket 29 on frame I so that it mayIollowthe lateral movement of pin '25 which naturally occurs when pivotbar Zliis rotated about its pivot pin 30.. Link arms. 3! and 3m arethreaded at each end as at alto engage threaded lugs 33 at their pivotbar end and threaded lugs '34 at their other ends. These lugs providepivotal connections to pivot bar 26. and cross members 3a and 1respectively by means of pins and studtli It will be observed that whenbelt 5 attempts to override rolls 4 to the left (toward side arm 2') itwill force roller it and braclzet l8 IateraHy Eoutward against thetension of spring 31 until bracket [0 depresses plunger l6 of switch "H.Spring "31 is normally under tension to keep bracket 10 snug againststop piece 38 welded to frame 'I at 38a; it is attached between stoppiece 38 and a projecting lug 99 0f bracket 10. This switch will causemotor 18 to rotate in such a direction to force the adjacent'end 4B ofbar. away from motor "and sincebar 28 pivots about its pin this actionwill cause link 3| and consequently cross member 1 to move away frommotor I! and in this direction belt 5 will be forced toward side "arm 2adue to the changed 181 ment of roll 6. At the same instant link Ha willbe moved toward motor 18 under the action of end 401; of bar 26 tocausetop cross member 3a and troughing rolls 4a to be 'out'of lateralalignment in an opposite direction from member 1 and thereby contributeto moving belt 5 in a G1 rection away from roller 8 and toward side arm2a. Belt under the influence of members 1 and 3a and their respectiverolls 6 and 4a will gradually move away from roller 8, and will continueuntil roll 6 has moved to a set angle, at which time an extension 4| ofcross member I will strike against cut off switch 42a mounted on sidearm 2. Switch 4211 stops the flow of electric current to motor 18 forany further rotation in the direction in which it has been operating.Belt 5 may, however, continue its gradual movement toward the roller ofbracket [0a on the opposite side arm 2a. When this happens, a switch Haon this side will operate in the same manner as before except here itwill cause the direction of rotation of motor l8 to reverse andconsequently gradually reverse the positions of members I and 3a untilthey have moved sufficiently to permit extension 4| to strike against asecond cut off switch 42 and again stop motor i8 from further rotationin that direction.

In examining structural details it will be seen that roll 6 isjournalled in end pieces 43 depending from cross member I at the extremeends thereof, while troughing rolls 4a are journalled in the end pieces44 of member 3a as well as intermediate pieces 45 and these rolls 4a arealigned in a conventional troughing arrangement. Cross members 3a and lare supported in space by means of a turntable structure 46 whichincludes cross struts 41 fastened between side arms 2 and 2a of frame 1.Plate 48 of turntable 46 fits snugly but in sliding relation betweenbottom plate 49 of cross member 3a and top'plate 50 of cross member 1.stud 5| is welded to channel 52 and plate 49 of top cross member 3a andthis stud has a nut 53 locked thereto on its threaded end by means ofset screw 54. The relationship of parts here is such that top member 3aand stud 5! may turn in central opening 55 of turntable 46, and bottomcross member I may turn about stud 5| and on nut 53.

A lubrication fitting 56 is threaded into plate 49 to permit insertionof lubricant for plates 49 and 50 to provide for easy turning betweenthese plates and turntable 48. This lubricant will also find its waythrough openings 55 and 51 into pocket 58 of nut 53 so that the slidingcontact between cross member I and nut 53 may be lubricated.

From the foregoing description it will be readily seen that there hasbeen produced such a device as substantially fulfills the objects of theinvention as set forth herein.

While this specification sets forth in detail the present and preferredconstruction of this invention, still in practice such deviations fromsuch detail may be resorted to as do not form a departure from thespirit of the invention, as defined in the appended claims.

Having thus described my invention, what is claimed as new and usefuland is desired to be secured by Letters Patent is:

1. A self-aligning carrier comprising spaced rolls including a troughingroll and a carrier roll, a continuous conveyor belt riding over saidtroughing roll in one direction and over said carrier roll in theopposite direction; said troughing roll and said carrier roll beingpivoted for belt adjusting movement, a link associated with each roll, apivot bar connected near each end to one said link, the pivot for saidpivot bar being intermediate said end connections, an electric powerunit operatively connected to one end A depending of said pivot bar sothat operation of said electric power unit will cause said links to movein opposite directions thereby causing said troughing roll and saidcarrier roll to pivot in opposite directions and cause movement of theconveyor belt axially of said rolls; a normally-off switch associatedwith the edge of said conveyor belt and operative to start said electricpower unit when said conveyor belt creeps out of alignment with saidspaced rolls.

2. A self-aligning carrier comprising spaced rolls including a troughingroll and a carrier roll, a continuous conveyor belt riding over saidtroughing roll in one direction and over said carrier roll in theopposite direction; said troughing roll and said carrier roll beingpivoted for belt adjusting movement, a link associated with each roll, apivot bar connected near each end to one said link, the pivot for saidpivot bar being intermediate said end connections, an electric powerunit operatively connected to one end of said pivot bar so thatoperation of said electric power unit will cause said links to move inopposite directions thereby causing said troughing roll and said carrierroll to pivot in opposite directions and cause movement of the conveyorbelt axially of said rolls; a normally 01f switch associated with theedge of said conveyor belt and operative to start electric'power unitwhen said conveyor belt creeps out of alignment with said spaced rolls,a limit switch associated with said carrier roll and operative to shutoff said electric power unit when said roll has pivoted through apredetermined angle.

3. A structure for a self-aligning carrier comprising a frame, sidewalls on the frame, cross members connecting to said side walls in rigidrelation, one cross member including spaced struts, a center plateconnected between said struts, a central opening in said plate, a troughing roll bracket including a bottom plate and a depending stud restingon said center plate, a troughing roll on said bracket, a carrier rollbracket including a top plate with a central opening abutting saidcenter plate, a carrier roll on said carrier roll bracket, said studprojecting through the central openings in said center plate and saidtop plate and having a nut locked on the free end thereof whereby topermit said troughing roll bracket and said carrier roll bracket topivot about the axis of said stud; a continuous conveyor belt having oneflight car ried by said troughing roll and the other by said carrierroll; a motor unit including a lead screw pivoted to said frame, a pivotbar pivoted to said frame intermediate the length of the bar, a threadedsleeve pivoted to one end of said pivot bar, said lead screw engagingsaid sleeve in actuating relation; a link connected at each end of saidpivot bar at their one end, one of said links pivotally connected at itsother end to said troughing roll bracket, the other link being pivotallyconnected to said carrier roll bracket; the motor unit, pivot bar,links, and brackets being so connected that operation of the power unitwill cause the troughing roll bracket to move in one direction about theaxis of its stud and yet cause the carrier roll bracket to move in theopposite direction about the axis of said stud at virtually the samerate of speed, and a switch engageable by said belt to actuate saidmotor unit. 4. A structure for a self-aligning carrier comprising aframe, side walls on the frame, rolls mounted in said frame, a conveyorbelt riding on said rolls in longitudinal alignment, cross membersconnecting to said side walls in rigid relation, one cross memberincluding spaced struts, a center plate connected between said struts, acentral opening in said plate, a troughing roll bracket including abottom plate and a depending stud resting on said center plate, atroughing roll in said troughing roll bracket, a carrier roll bracketincluding a top plate with a central opening abutting said center plate,a carrier roll in said carrier roll bracket, said stud projectingthrough the central openings in said center plate and said top plate andhaving a nut locked on the free end thereof whereby to permit saidtroughing roll bracket and said carrier roll bracket to pivot about theaxis of said stud; spaced rolls supported by said frame, an electricmotor unit including a lead screw pivoted to said frame, a pivot barpivoted to said frame intermediate the length of the bar, a threadedsleeve pivoted to one end of said pivot bar, said lead screw engagingsaid sleeve in actuating relation; links connected at each end of saidpivot bar at their one end, one of said links pivotally connected at itsother end to said troughing roll bracket, the other link being pivotallyconnected to said carrier roll bracket; the electric motor unit, pivotbar, links, and brackets being so connected that operation of the powerunit will cause the troughing roll bracket to move in one directionabout the axis of its stud and yet cause the carrier roll bracket tomove in the opposite direction about the axis of said stud at virtuallythe same rate of speed; a bracket pivoted to said side arm and a beltguide roller journalled in said bracket, said roller and bracket movingoutward under the pressure of said belt when said belt creeps out oflongitudinal alignment with said spaced rolls to engage and close aswitch to actuate said motor unit.

5. A conveyor comprising a frame; troughing rolls; carrier rolls; acontinuous belt having its upper flight carried by said troughing rollsand its lower flight carried by said carrier rolls; means mounting atleast one set of troughing rolls for pivotal movement about an axisperpendicular to said belt; means mounting a corresponding carrier rollfor pivotal movement about an axis perpendicular to said belt; anelectric motor operatively connected to said mounting means and adaptedwhen actuated to pivot said set of mounting rolls in one direction andsaid corresponding carrier roll in the opposite direction about saidaxes; a switch mounted adjacent one side of one flight of said belt andadapted to be closed upon contact with said belt to actuate said motorand pivot said set of troughing rolls and said corresponding carrierroll to positions to cause said flights of said belt to travel in adirection away from said switch.

6. A conveyor comprising a frame; troughing rolls; carrier rolls; acontinuous belt having its upper flight carried by said troughing rollsand its lower flight carried by said carrier rolls; means mounting atleast one set of troughing rolls for pivotal movement about an axisperpendicular to said belt; means mounting a corresponding carrier rollfor pivotal movement about an axis perpendicular to said belt; anelectric motor operatively connected to said mounting means and adaptedwhen actuated to pivot said set of mounting rolls in one direction andsaid corresponding carrier roll in the opposite direction about saidaxes; a switch mounted adjacent one side of one night of said belt andadapted to be closed upon contact with said belt to actuate said motorand pivot said set of troughing rolls and said corresponding carrierroll to positions to cause said flights of said belt to travel in adirection away from said switch; a limit switch adapted to be engagedupon pivotal movement of said pivotally mounted rolls and preventfurther pivotal movement thereof; a second switch mounted adjacent theother side of said one flight of said belt and adapted when contacted bysaid belt to close and actuate said motor in reverse direction to pivotsaid set of troughing rolls and said corresponding carrier in directionsopposite to that caused by closing of said first switch.

7. A conveyor comprising a frame; troughing rolls; a carrier roll; abelt adapted for movement over the troughing rolls and the carrier roll,the direction of movement over the troughing rolls being opposite fromthat over the carrier roll; means mounting the troughing rolls in saidframe for pivotal movement about an axis perpendicular to said belt;means mounting the carrier roll in said frame for pivotal movement aboutan axis perpendicular to said belt; and means responsive to lateralmovement of the belt for causing pivotal movement of the troughing rollsin one direction about said axis while simultaneously causing pivotalmovement of the carrier roll in the other direction.

R. G. LE TOURNEAU.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,770,957 Veale July 22, 1930 2,075,111 Gulliksen et al Mar.30, 1937 2,304,843 Nordquist Dec. 15, 1942 FOREIGN PATENTS NumberCountry Date 26,967/30 Australia June 4, 1931

